Research Article, Int J Cardiovasc Res Vol: 9 Issue: 1

Factors Affecting Outcome of Rescue Percutaneous Coronary Intervention in Acute Myocardial Infarction

Mohamed Salah El Din^1*, Mohamed Mahmoud², Mohammed Abdel Ghany³, Ali A Elsharkawi⁴ and Amira Abd El Razik⁵

¹Professor of Cardiovascular Medicine Faculty of Medicine, Al-Azhar University, Assuit.

²Assistant professor and Head of Cardiology Department Faculty of Medicine, Al-Azhar University, Assuit.

³Assistant professor of Cardiovascular Medicine Faculty of Medicine-Assuit University, Assuit.

⁴Lecturer of Cardiology, National Heart Institute, Cairo, Egypt.

⁵M.Sc Cardiology, Faculty of Medicine, Al-Azhar University, Assuit.

*Corresponding Author: Dr. Ali Elsharkawi
Lecturer of Cardiology, National Heart Institute, Cairo, Egypt
Tel: +201140000922
E-mail: ali.elsharkawi@yahoo.com

Received: February 17, 2020 Accepted: April 20, 2020 Published: April 27, 2020

Citation: Salah El Din M, Mahmoud M, Ghany MA, Elsharkawi AA, El Razik AA (2020) Factors Affecting Outcome of Rescue Percutaneous Coronary Intervention in Acute Myocardial Infarction. Int J Cardiovasc Res 9:1.. doi: 10.37532/icrj.2020.9(1).394

Abstract

Keywords: Rescue percutaneous coronary intervention; ST-segment elevation myocardial infarction; Major adverse cardiac events

Introduction

PCI, if performed in a timely fashion, is the recommended reperfusion strategy for patients with recent acute STEMI [1].

Reperfusion therapy by successful PCI has contributed to an important reduction in mortality after AMI by limiting myocardial necrosis and preservation of LV function [2].

Rescue PCI is defined as PCI within 12 h after failure of fibrinolytic therapy for patients with continuing or recurrent myocardial ischemia [3].

Rescue PCI remains an infrequent procedure in different data registry analysis because many clinicians do not assess the success of reperfusion in patients with STEMI, who receive thrombolytic analysis, and only a minority are candidates for rescue PCI due to failed thrombolytic therapy [4].

Still not all hospitals in several places in the world could offer a 24 hour 7 days a week primary PCI service to patients or an available primary PCI with an acceptable transfer time, in Egypt we still have some areas with no such capability and thrombolytic therapy is still given in such places as an initial management.

Only limited information on the major predictors of this outcome is available, but in general rescue PCI after failed thrombolytic treatment was associated with a statistically significant reduction in the incidence of major adverse cardiac and cerebrovascular events, as compared with either repeated thrombolysis or conservative management [5].

This study aimed to evaluate factors affecting Rescue PCI in STEMI as regard incidence of MACE on early after PCI in hospital & after six months of intervention.

Patients and Methods

Patients

120 patients with STEMI without response to fibrinolytic therapy who are suitable for Rescue PCI.

Study design: observational cross- sectional study.

Study site: The study was conducted in the coronary care unit (CCU), cardiology department, at Assiut University Hospital and Al Azhar university.

Study population: Study group was selected according to the following criteria:

All Patients were admitted with acute STEMI within 12 hours of chest pain and were given fibrinolytic therapy (streptokinase), (1.5million units over 60 minutes), who Lack ST-segment resolution (defined as less than 50% reduction in ST segment elevation in the lead showing the greatest ST-segment elevation measured at the isoelectric line) at Electrocardiogram at 90 minutes post thrombolytic therapy with or without chest discomfort.

Methods

All patients were subjected to informed consent, detailed clinical history taking, complete general and cardiac examination, full laboratory data, 12-lead resting Electrocardiography, complete transthoracic Echocardiographic examination and Coronary angiography & PCI.

History taking

At admission, the patients’ demographic information (age, sex, and occupation) and risk factors was taken from all members of the study group with special emphasis on:

The intervals between the onset of symptoms and hospital admission and between hospital admission and PCI. History of hypertension, History of diabetes mellitus History of ischemic heart disease (IHD). Dyslipidemia& family history of IHD and smoking.

Clinical Evaluation

All patients were assessed clinically, including the evaluation of cardiovascular risk factors (hypertension, peripheral vascular disease, and congestive heart failure); with assessment of patient Killip class.

Electrocardiographic (ECG) evaluation

For a patient to qualify as having a STEMI, in addition to reported angina, the ECG must show new ST elevation in two or more adjacent ECG leads. This must be greater than 2 mm (0.2 mV) for males and greater than 1.5 mm (0.15 mV) in females if in leads V2 and V3 or greater than 1 mm (0.1 mV) if it is in other ECG leads. Also, a recent left bundle branch block was considered the same as ST elevation. In early STEMIs there may just be peaked T waves with ST elevation developing later [6].

The changes of wall infarction are specifically seen in the leads overlying the infarct area. Thus, in inferior wall infarct changes are seen in leads II, III, AVF; in anterior infarct in lead V1-V4 and in anterolateral infarct in lead I, AVL and V5-V6. RV infarct is diagnosed by ST elevation in V3R and V4R [7].

Laboratory assessment

Routine laboratory investigations including, random blood sugar and lipid profile, kidney function tests, liver function tests, cardiac markers.

Transthoracic Echocardiography evaluation

Complete two-dimensional (2D) and Doppler color flow examinations were performed with the Philips, HDI 5000 (Sonos) equipped with Harmonic 53 transducer. Left ventricular function was assessed using Transthoracic Echocardiography (TTE) before coronary angiography &six months after PCI. Complete TTE studies were performed according to the last recent guidelines for all patients. Echocardiographic images were acquired from the standard views [8]. The echocardiographic study also included the assessment of left and right-side atrial and ventricular size, contractility and function as well as the detection of valvular stenosis or regurgitation by color Doppler.

Invasive Coronary angiography & PCI

Coronary angiography in multiple views was performed according Judkins or Sones Standard technique. At least four views for evaluation of Left Main (LM) coronary artery, Left Anterior Descending (LAD), Left Circumflex (LCX) and Right Coronary Artery (RCA) was performed. Interpretations of coronary angiogram was done by visual estimation by two cardiologists to assess TIMI flow & the severity of coronary artery disease, which was graded according to Vessel score.

Vessel score: This is the number of vessels with a significant stenosis (for left main coronary artery 50% or greater and for others 70% or greater reduction in luminal diameter). Score ranges from 0 to 3, depending on the number of vessels involve. Left main coronary artery was scored as single vessel disease [9].

Score 0 = no vessel involvement. Score 1 = single vessel involvement. Score 2 = double vessel involvement. Score 3 = triple vessel involvement.

B. TIMI flow grades

TIMI flow grade (Table 1) [10].

Table 1: BTIMI flow grade.

The study subjects were divided into two main groups

*Group I: included patients who die or have complications, including serious arrhythmias (ventricular fibrillation and ventricular tachycardia), heart failure, bleeding of the artery that requiring blood transmission, or a second PCI of the same vessel during hospital stay and the first six months follow up.

*Group II: patients that have no complications.

Statistical Analyses

The collected data was entered and edited using SPSS version 20 statistical software (IBM Corporation and its licensor 1989, 2011). Descriptive statistics of the collected data was done for most variables in the study using statistical measurements. Frequency tables, graphs, percentages, means, standard deviations and multiple logistic regression analysis were used

Results

The study included 120 patients with acute STEMI admitted to CCU, cardiology department at Assiut University Hospital during the period from June 2015 to June 2017.

Study Population

The mean age was (53.60 ± 11.26), two thirds (75%) of patients were males.35% had diabetes mellitus, 30% were hypertensive. Smokers were 60% of all patients, dyslipidemia was present in10% of patients, 15% whose had family history of IHD and 22.5% patients were IHD (Table 2).

Table 2: Demographic characteristics of patients undergoing Percutaneous Coronary Intervention (PCI) for myocardial infarction. No. (n= 120).

Time from symptom onset to admission

The Mean time from symptom onset to admission was 6.85 ± 4.20 hours. 45% patients presented at CCU within 3 to 6 hours from symptoms onset, 40% were presented at CCU within more than 6 hours from symptoms onset, meanwhile 15% patients presented in the first 3 hours of chest pain (Table 3)

Table 3: Time from symptom onset to admission.

Target segment of STEMI according to ECG

Anterior MI was affected 52.5% patients, where 22.5% patients had inferior MI, 7.5% patients had inferior posterior. MI, 5% patients had inferior lateral MI, 10% patients had inferior right MI and only one patient had combined anterior and Inferior MI that represent 2.5% (Table 2).

Rescue PCI

The mean time from diagnosis of failed reperfusion till the start of intervention in the Cath lab was 5.58 ± 2.86 hours. 5% patients had time of less than 3 hours, in contrast the majority of patients 72.5% had time between 3 to 6 hours meanwhile 22.5% patients had time between more than 6 hours. Transfemoral approach was done in 90% of patients.

As regards to target vessel lesion affection, LAD was in (47.5%) of the cases, RCA was in 32% of the cases, OM affection was found in 7.5% patients. For combined lesions affection there were LAD and RCA in 5% of patients, only 2.5% patient in each LCX-OM, RCA-OM and RCA-LCX respectively. Implantation of Bare-Metal Stent (BMS) was performed in 50% of the cases.

In hospital outcome

72.5% patients pass hospital stay without any complications, but there were reported cases of angina and arrhythmia as 7.5% and 12.5% respectively. (2.5%) was reported of death. Also, there were reinfarction and acute renal failure as 2.5% for each (Table 4).

Table 4: Follow up during hospitalization, bare metal stent, drug eluting stent.

Six months outcome

Heart failure occurs in (12.5%) of cases. unstable angina was reported in (10%) of cases, also death was reported in (10%) of the cases. only 2.5% case had stroke. no reported case of Target Vessel Revascularization (TVR) (Table 5).

Table 5: Follow up after 6 months.

Follow up at hospital

Gender had no significant effect on MACE after rescue PCI (P value>0.05).

The incidence of complication was more frequent in smokers and hypertensive patients (63.6% versus 58.6%) and (36.4% versus 27.6%) respectively with no significant statistical difference (p value>0.05).

No significant association were found between DM, dyslipidemia, family history of IHD and history of IHD and MACE after rescue PCI between two groups (P value>0.05)

Before PCI, TIMI flow grade 0 was higher in group 1 than group (72.7%) and (31%) respectively with statistically significant difference as regard incidence of MACE (P value<0.05). There was no statistically significant difference between the two groups as regard to TIMI flow I, II (P value>0.05). After PCI, patients had TIMI flow grade III with favorable outcomeThe incidence of complications was more frequent in smokers (64.3% versus 57.7%) with no significant statistical difference (p value>0.05). No statistically significant association were found between DM, HIN, dyslipidemia, family history of IHD and history of IHD as regard incidence of MACE after rescue PCI between two groups (P value>0.05).

Before PCI, TIMI flow grade 0 was higher in group 1 than group (64.3%) and (30%) respectively with statistically significant difference (P value<0.05). There was no statistically significant difference between the two groups as regard to TIMI flow I, II before PCI (P value>0.05).

Post PCI, patients had TIMI flow grade III with favorable outcomes in group 2 (100%) than group 1 (85%) but with no statistically significant difference (P value<0.05).

Implantation of BMS was associated with more incidence of complications (71.4%) with statistically significant difference between two groups (P value<0.05).

EF is an important predictor factor of MACE post rescue PCI as EF post PCI, in group 1was (40.40 ± 6.43) and in group 2 was (56.31 ± 7.13) with statistically significant difference (P value<0.05) (Table 6).

Table 6: Multiple logistic regression analysis for risk factors of complications during hospitalization, bare metal stent, diabetes mellites, left anterior descending.

Multiple logistic regression analysis of risk factors as regard incidence of MACE during hospital admission

As regards to risk factors affecting outcome of rescue PCI, variables were chosen according to variables in previous studies that have been studied to influence the incidence of MACE in myocardial infarction as well as observed variables in our clinical practice that showed influence or relationship to the MACE. Time from symptom onset to admission, time from diagnosis of failed reperfusion till the start of PCI, TIMI flow grade 0 at time of diagnostic CA and implantation of BMS were the most independent risk factors associated with MACE of rescue PCI (P value <0.05)(OR>1) (Table 4).

LVEF was considered a protective factor on MACE following PCI. (P value<0.05) (OR<1 as shown in (Table 7).

Table 7: Multiple logistic regression analysis for risk factors of complications after 6 months, BMS, DM, LAD.

Multiple logistic regression analysis of risk factors as regard incidence of MACE after 6 months

Time from diagnosis of failed reperfusion till the start of PCI, TIMI flow grade 0 before PCI and implantation of BMS were the most independent risk factors associated with MACE of rescue PCI (P value<0.05) (OR>1). LVEF was considered a protective factor on MACE following PCI P value<0.05) (OR<1) (Table 8).

Table 8: Follow-up during hospitalization and after 6 months. No. (n= 120).

Discussion

The current study sought to identify factors affecting MACE in patients who underwent rescue PCI for STMEI on short term follow up (early after PCI in hospital &after six months of intervention) in our locality.

Gender had no significant effect on MACE during hospitalization stay and 6 months follow up [11]. However, some studies have found higher mortality rates in women than in men, female gender as a risk factor for mortality is still debatable [12]. The influence of female gender on outcomes might be explained by differences in coronary physiology, anatomy and in cardiovascular risk factors or associated with other causative factors such as hormonal status, endothelial dysfunction, micro-circulation disorders, etc. [13]. Moreover, the absence of such a higher risk in females’ participants in our study emphasizes the benefits of rescue PCI.

Age is a very powerful determinant for the clinical outcome in ACS patients after PCI [14]. We found that incidence of MACE post PCI during hospital stay and 6 months follow up was not related with age. Since old patients with STEMI did not undergo rescue PCI in community practice and were prescribed with pharmacological treatment instead. Also, small sized population may be another reason [15,16].

As regarding to risk factors of acute STEMI, we found that DM had no significant effects on the incidence of MACE in this study, however DM is associated with a higher risk of mortality after PCI in STEMI patients [17]. As, diabetic patients have platelets dysfunction which contribute increased risk of mortality in these patients, also poor response to smoking is considered a major risk factor for coronary artery disease [18-20]. The importance of smoking in the incidence of MACE after rescue PCI is a matter of concern. In this study, however incidence of complication more frequent in smokers (63%), smoking did not have any negative effects on MACE and this concordant with Sadrnia et al. [21]. study. However, a previous research reported better reperfusion rate after PCI in smokers [22]. So, question about why smokers with less mortality rate compared to non-smokers after PCI is more interesting than its answer. Reasons suggested for this smoking paradox could be younger age, more favorable clinical and angiographic profile and less damage to microvascular function in these patients after PCI. However, many other studies had different results. The study Jang et al. [23] showed that individuals who continue smoking after PCI experienced significantly poor outcomes compared to patients who had never smoked in concluded that longterm risks of myocardial infarction and death are higher in smokers than in nonsmokers after PCI.

The corner stone in our study is to identify factors affecting Rescue PCI in STEMI as regard incidence of (MACE) on short term follow up (during hospitalization and after 6 months after PCI). We found that time from symptom onset to admission was considered an independent risk factor associated with complications after rescue PCI (P value<0.05) (OR>1). Time from symptoms onset to presentation at hospital is particularly important for patients with STEMI. Aside from the association of longer ischemic times with myocardial damage and more adverse clinical consequences, the effectiveness of reperfusion therapy depends on this interval, with the therapy having greatest benefit for patients who present with the shortest delay presentation [24,25]. Most patients in the present study (45%) had time from symptom onset within 3-6 hours. which is considerably longer than times reported from REACT, MERLIN, and RESCUE trials which was 2, 3, 3 hours respectively. Similarly, in Tungsubutra et al. [26] study median time from onset of chest pain to emergency room presentation was a lengthy 160 minutes. But our result was concordant with Salem et al. [27], study that shown most patients had time from symptoms onset to admission within 6 hours. Moreover, this delayed presentation likely results from one or more of the following: lack of patient awareness, absence of an established ambulance system, traffic related issues, and other multifactorial logistical barriers.

Another an important risk factor affecting MACE was the time from diagnosis of failure of fibrinolysis until the start of intervention (PCI). In our study, the mean time from diagnosis of failure of fibrinolysis until the start of intervention was 5.58 ± 2.86 hours which was considered an independent risk factor affecting on MACE post PCI (P value<0.05) (OR>1). a strong association between the time to reperfusion treatment and mortality for patients with STEMI [28]. Every 30 min delay from symptom onset to PCI increases patients’ risk of death [29]. This time seems to be longer than time reported from Salem et al. [27] study, in which the mean time was 3.1 ± 1.2 hours. Also, in MERLIN trial, the mean time from 60 minutes ECG (diagnosis of failure) to coronary angiography was 1.5 ± 0.5 hour. In REACT trial the mean time from 90 minutes ECG to rescue PCI was 5 ± 3 hours. The difference between our results and these trials is related to the diagnosis, education of the patients, and long transport time.

TIMI flow is one of the important factors in determining the outcome of PCI in patients with STEMI. Good TIMI flow at the time of diagnostic angiography is a determinant of MACE in patients undergoing rescue PCI. Patients with TIMI flow grade 3 were expected to have higher survival rates and fewer complications following rescue PCI [30]. This current study reveal that TIMI flow grade 0 at the time of diagnostic angiography was independent risk factor of MACE after PCI value<0.05) (OR>1), and TIMI flow grade 3 was associated with reduced MACE in patients receiving rescue PCI, as 96.6% of our cases had TIMI flow grade 3 post PCI pass without complication, similarly in MERLIN trial (85%) of patients had TIMI 3 flow post PCI.

A major determinant of patients’ survival and the incidence of MACE after rescue PCI is LVEF. Better LVEF is associated with improved survival. On the other hand, low LVEF is associated with higher incidence of MACE [31]. In the current study, low LVEF had statistically significant effect on MACE in patients undergoing rescue PCI. (P value<0.05) (OR<1). This came in agreement of in Vakili et al. [3] study concluded that left ventricular function improved more in patients who underwent rescue PCI not primary PCI.

One of the major finding in this study, implantation of BMS was strong independent risk factor associated with MACE post PCI value<0.05) (OR>1). The most frequent reason for BMS use was related to concerns on Dual Anti-Platelets Therapy (DAPT) compliance [32]. This was followed by the presence of a target vessel with a large reference diameter, treatment of patients with acute STEMI , concerns related to reimbursement and planned non cardiac surgery within 1 year after stent implantation, and according to our locality, the health insurance did not reimbursement for DES, but only to BMS at that time [33].

As regard to follow our patients during hospital stay, most patients (72.5%) pass hospital stay without any complications, but there were reported cases of angina and arrhythmia (7.5%) and (12.5%) respectively. 2.5% cases reported for death. No reported cases of target vessel revascularization (TVR) and major bleeding. This came in agreement of The MERLIN study Sutton et al. [34] and the REACT Gershlick et al. [35] trial demonstrated that rescue PCI, had improvement in the composite end point of death, reinfarction, stroke, and severe heart failure. But, in both of these trials, rescue PCI was associated with increased bleeding, which has been demonstrated to be an adverse prognostic indicator [33]. Similarly, in Salem, et al. [27] study, no mortality was reported also no reported cases of reinfarction, heart failure, stroke, recurrent ischemia, need for urgent intervention, arrhythmia, or major bleeding during the hospital stay. In contrast, in hospital mortality rate in Tungsubutra et al. [26] was (8.3%) which was higher than data from prior observational studies (3.9-6.5%) conducted in developed countries Shavelle et al. [36] but comparable to the 10% rate reported from Pakistan [37].

This difference in findings may be due to failure to restore reperfusion at the microvascular level, despite establishment of normal epicardial coronary flow. In addition, differences in patient baseline characteristics, logistical barriers and challenges present in developing countries may explain these differential outcomes.

As regarding to follow up our cases after 6 months post PCI, angina requiring hospitalization was reported in 10% and this came in agreement of Salem et al. [27] study in which angina reported 13% of the cases. In addition there were no reported cases of TVR in our cases but, TVR was done in 3% in Salem et al. [27] study that were concordant with the results of the MERILN trial Sutton et al. [33] in which 6.5% had TVR in rescue PCI. No reported cases of TVR in our study may due to uses of small length stents and implantation of DES may be play an important role.

Also, heart failure occurs in 12.5% of our cases which was in concordant with Saem et al. [27] study that concluded cases of congestive heart failure occurred 10%. The meta-analysis done by Wijeysundera et al. [38] which included six trials (including REACT, MERLIN and RESCUE trials) reported significant reduction in the relative risk (RR 0.73, 956% CI 0.54-10.00) of heart failure in the rescue PCI group after following up period six months. Moreover, there were 10% reported case of mortality in our cases and, In REACT trial, mortality was (6.2%). In contrast, there were no reported cases of mortality in Salem et al. [27] study.

This difference of our results and other trials may contributed due to poor compliance of our patients to treatment programs, delay presentation and seeking medical advice, prolonged ischemic time and prolonged door to balloon time, low social economic that need to prolonged time for DAPT.

Conflicts of interest

No conflict of interest has been declared.

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